The GstClockID to wait on
a pointer that will contain the jitter, can be NULL.
the result of the blocking wait. GST_CLOCK_EARLY will be returned if the current clock time is past the time of id, GST_CLOCK_OK if id was scheduled in time. GST_CLOCK_UNSCHEDULED if id was unscheduled with Clock.idUnschedule.
MT safe.
Perform a blocking wait on id. id should have been created with Clock.newSingleShotId or Clock.newPeriodicId and should not have been unscheduled with a call to Clock.idUnschedule.
If the jitter argument is not NULL and this function returns GST_CLOCK_OK or GST_CLOCK_EARLY, it will contain the difference against the clock and the time of id when this method was called. Positive values indicate how late id was relative to the clock (in which case this function will return GST_CLOCK_EARLY). Negative values indicate how much time was spent waiting on the clock before this function returned.